Patent Document 1 discloses a multi-joint robot that acts according to a manipulation of an operator. The multi-joint robot described in Patent Document 1 (JP 2010-269419 A) includes a multi-joint arm, a manipulation stick connected to the multi-joint arm, a force sensor connected to the manipulation stick, and a control device controlling a motion of the multi-joint arm.
In the multi-joint robot described in Patent Document 1, the force sensor detects a direction and a size of a force inputted by a user through the manipulation stick. The direction and the size of the force are converted into an amount of a motion of the multi-joint arm that is operated by the control device.
In the multi-joint robot described in Patent Document 1, the multi-joint arm is operated under a prerequisite that a reference point (i.e. zero point) of a force detected by the force sensor is set accurately.
However, in the multi-joint robot described in Patent Document 1, if a zero point adjustment in which the reference point of the force sensor is set is performed while an object is in contact with the manipulation stick or the force sensor, the reference point of the force sensor becomes inaccurate.
Therefore, the conventional technology is required to set the reference point in the zero point adjustment while a force is not exerted on the force sensor.